以陽離子交換法合成硒化物奈米棒

Abstract

在此篇論文中我們成功地合成出多種不同成分之單晶硒化物奈米棒，例如:CdSe、ZnSe，且利用陽離子交換法合成出Cd1-xZnSe奈米棒。而在此也將討論研究和比較各種奈米棒之成長機制。透過一個典型的製程可以成功利用纖維素輔助之化學還原法合成出單晶硒奈米棒，且將Ag+離子直接加入硒奈米棒水溶液中,即可直接獲得高產率之Ag2Se奈米棒。接著透過陽離子置換法可將Ag2Se中之Ag+離子分別地換成Zn2+離子和Cd2+離子，而得到單晶結構之ZnSe和CdSe奈米棒。利用此法合成出之硒化物奈米棒直徑約50~70nm且長度分佈在500~800，非常相近於起始之硒奈米棒。更進一步的利用陽離子交換法可以合成出三元之硒化物奈米棒，如Cd1-xZnxSe，且其成分之控制和其光學性質也在此篇論文被探討研究。此合成之方法可以簡單應用在製備各類之硒化物和硫化物之奈米結構。

In the present work, we have successfully synthesized a variety of selenides nanorods including CdSe, ZnSe and some Cd1-xZnxSe alloys through a cation exchange approach. The growth mechanism for these selenide nanorods was also studied, compared, and discussed. In the typical process, single crystalline nanorods of Se were first synthesized through a carboxylmethyl cellulose-assisted chemical reduction approach. A direct incorporation of Ag+ into Se nanorods was then conducted by the addition of AgNO3 into the Se nanorods solution, resulting in the formation of Ag2Se nanorods. Further replacement of Ag+ of Ag2Se nanorods with Cd2+ and Zn2+can be achieved by the cation exchange reactions, leading to the growth of single-crystalline CdSe, and ZnSe nanorods, respectively. The as-synthesized selenides nanorods have diameters of 50-70 nm and lengths varying from 500-800 nm, similar to those of the starting Se nanorods. By using this method in our experiment, we may further obtain ternary alloyed selenide nanorods, for example, Cd1-xZnxSe, to study the effect of cation composition on the resulting in optical properties of nanorods. The present synthetic approach can be readily applied to prepare other selenide- and sulfide-based nanostructures.